I read and commented on your original essay, and I believe this version is much stronger. It's a very compelling story and the structure, how you went from helpless to inspired to helpful, is really well done and clear.
I just have a fewwww stylistic points. Keep in mind that your essay is very good as it is, so these are just nitpicking things.
1. The only substantive criticism I have is the word "incorrigible." Whatever your feelings are for your mother, that word has a negative connotation that I think you want to stay away from, or else you appear too judgmental. Remember, we, and the admissions officers, don't know your mother, so we're not entirely sure the real reason (sounds like you're not either) why she got addicted to pain medication, but you don't want to paint her as a totally unsympathetic character (although she may very well be). It's not impossible that the admissions officers may know someone that was likewise addicted to pain meds, so you don't want to include such polarizing language. Her incorrigible nature is already apparent from your essay, so I think it has the potential to detract from your essay more than any possible benefits it has.
By working with Erik, I realized that if I instead invested my energy into making a difference in people’s lives rather than trying to fix my incorrigible mother, I could make a meaningful impact on people’s lives.
I would try to find a way to really emphasize this point, as it is one of the most crucial lines in your essay. It describes your turn-around moment and it also indirectly states what happened with your mother. I had to reread your essay to find the exact turn-around moment.
3. The Oxford comma! Learn it, use it, love it. There are at least two instances in your last big paragraph where it should be used.
4. The sentence with the "bridging the communication gap..." I know I suggested removing the specific internships/positions where you did those, but I think you just want to add something that says that it was from your past experience. For example, "The responsibilities I have had thus far -- whether it was bridging the communication gap between Hispanic families and teachers, coordinating a pro bono legal clinic (or plural if it was more than one), to help immigrants navigate the complex world of immigration law, or writing briefs to persuade the U.S. government to let a father of three U.S. citizen children remain in the united states -- have guided me towards, and eventually into, a career in immigration law."
There are a few grammatical errors (commas, mostly) that could be included, as well as some sentences that could be shortened to be more clear, but otherwise, very good essay.
Padilla v. Kentucky! I wrote a memo of law on that.
edit: I would take out the last two sentences that you mentioned. The conclusion without them has a #dropthemic feel to it and I think that the readers will get the substance of those last two sentences by reading the rest of your statement, and come to that conclusion for themselves, which is a far more effective tactic. I'd also separate the compound sentence.
I know that what I am doing now is not the end of the road for me—I want to practice immigration law, and I will not rest easy until I can argue cases in front of an Immigration Judge. I am not the same “me” as before, who put dreams on the backburner, and was consumed with trying to change things and people I had no control over. I understand now what I do have control over is me and my dreams, and I eagerly welcome law school to achieve those dreams.
Although “Brown Eyed Girl” no longer resonates throughout my parent's home, the difference now is that I am at peace with understanding it most likely never will. I am finally free from the restraining guilt that held me back from achieving my dreams, and am eagerly welcoming the challenge of law school.